Galvanic or sacrificial anodes are widely used for cathodic corrosion protection of underwater structures. Such sacrificial anodes create the galvanic current which protects the submerged structure, and are designed to corrode sacrificially. They accordingly must be properly electrically connected to the structure and replaced at the end of their design life. Submerged structures such as pipelines, offshore platforms, piers, pilings, or marine risers, can be very deep, and such anodes are normally installed by divers, submersibles or remotely operated vehicles. Divers, submersibles, such as manned submarines, or sophisticated remotely controlled robotic submersibles are extremely expensive to operate, and this is particularly true as the depth increases. The latter systems use robotic arms and even a diver has less than normal dexterity, particularly in a diving suit at significant depth. Such restraints also make many tools or power tools difficult to use.
In addition to the constraints of the suit, submersible, or vehicle, environmental factors such as currents, visibility, bottom condition or bottom changes, bottom time, and many other factors, all make the placement and replacement of anodes difficult.
Strong currents have been known to tear away or dislodge carefully placed anodes. They have also been known to cause or at least transfer unwanted vibration to the structure being protected. The current is believed to cause a vortex on the downstream side of the anode or bracket supporting the anode or the structure. This is believed to cause the vibration and flutter which can lead to damage.
Many such submerged structures are cylindrical or tubular in shape. This is particularly true of deep water platforms. Anodes are often positioned to be generally parallel to but spaced from a tubular structure, both horizontally and vertically. The anodes also need to make good electrical contact with the structure.
It would therefore be desirable to have an anode and bracket assembly which could quickly be hung or fastened on and removed from underwater cylindrical structures, either circular or rectangular-in-section. It would also be desirable if the assembly could easily firmly be clamped to the structure and at the same time making good electrical contact with the structure. It would also be desirable to have an anode which is configured for vortex shedding in high currents thus reducing the forces and vibration on both the anode, its bracket assembly, and the structure.